drm/amdgpu: fix rb setting for CZ

Always set num_rbs to 2 for CZ.  The 1 RB parts are often harvest
configs.  The will get sorted out in mesa when we program
PA_SC_RASTER_CONFIG[_1].

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c

@@ -1983,6 +1983,7 @@ static void gfx_v8_0_gpu_init(struct amdgpu_device *adev)
 		adev->gfx.config.max_shader_engines = 1;
 		adev->gfx.config.max_tile_pipes = 2;
 		adev->gfx.config.max_sh_per_se = 1;
+		adev->gfx.config.max_backends_per_se = 2;
 
 		switch (adev->pdev->revision) {
 		case 0xc4:
@@ -1991,7 +1992,6 @@ static void gfx_v8_0_gpu_init(struct amdgpu_device *adev)
 		case 0xcc:
 			/* B10 */
 			adev->gfx.config.max_cu_per_sh = 8;
-			adev->gfx.config.max_backends_per_se = 2;
 			break;
 		case 0xc5:
 		case 0x81:
@@ -2000,22 +2000,19 @@ static void gfx_v8_0_gpu_init(struct amdgpu_device *adev)
 		case 0xcd:
 			/* B8 */
 			adev->gfx.config.max_cu_per_sh = 6;
-			adev->gfx.config.max_backends_per_se = 2;
 			break;
 		case 0xc6:
 		case 0xca:
 		case 0xce:
 			/* B6 */
 			adev->gfx.config.max_cu_per_sh = 6;
-			adev->gfx.config.max_backends_per_se = 2;
 			break;
 		case 0xc7:
 		case 0x87:
 		case 0xcb:
 		default:
 			/* B4 */
 			adev->gfx.config.max_cu_per_sh = 4;
-			adev->gfx.config.max_backends_per_se = 1;
 			break;
 		}